A Nonlinear Guidance Law for Impact Time Control

This paper discusses the problem of impact time control of an interceptor against a stationary target. A nonlinear guidance law is proposed with the interceptor heading angle variation as a function of the range to target. Closed-form expressions for the design parameters are derived for an exact analysis of the impact time. A feedback form of the guidance law is presented for addressing realistic implementation in the presence of autopilot lag. Using the closed-form expressions of the impact time, a cooperative guidance scheme is presented for simultaneous impact in a salvo attack. Extensive simulation studies are presented validating the analytic findings.

Optimal Guidance for Accurate Lunar Soft Landing with Minimum Fuel Consumption using Model Predictive Static Programming

In this paper the soft lunar landing with minimum fuel expenditure is formulated as a nonlinear optimal guidance problem. The realization of pinpoint soft landing with terminal velocity and position constraints is achieved using Model Predictive Static Programming (MPSP). The high accuracy of the terminal conditions is ensured as the formulation of the MPSP inherently poses final conditions as a set of hard constraints. The computational efficiency and fast convergence make the MPSP preferable for fixed final time onboard optimal guidance algorithm. It has also been observed that the minimum fuel requirement strongly depends on the choice of the final time (a critical point that is not given due importance in many literature). Hence, to optimally select the final time, a neural network is used to learn the mapping between various initial conditions in the domain of interest and the corresponding optimal flight time. To generate the training data set, the optimal final time is computed offline using a gradient based optimization technique. The effectiveness of the proposed method is demonstrated with rigorous simulation results.

UK guidance on the initial evaluation of an infant or an adolescent with a suspected disorder of sex development

It is paramount that any child or adolescent with a suspected disorder of sex development (DSD) is assessed by an experienced clinician with adequate knowledge about the range of conditions associated with DSD. If there is any doubt, the case should be discussed with the regional team. In most cases, particularly in the case of the newborn, the paediatric endocrinologist within the regional DSD team acts as the first point of contact. The underlying pathophysiology of DSD and the strengths and weaknesses of the tests that can be performed should be discussed with the parents and affected young person and tests undertaken in a timely fashion. This clinician should be part of a multidisciplinary team experienced in management of DSD and should ensure that the affected person and parents are as fully informed as possible and have access to specialist psychological support. Finally, in the field of rare conditions, it is imperative that the clinician shares the experience with others through national and international clinical and research collaboration. © 2011 Blackwell Publishing Ltd.

Career Planning in Spain: Do temporary contracts delay marriage and motherhood?

The aim of this paper is to find an empirical connection between the impressive increase in the use of temporary contracts in Spain and the observed increase in age at marriage and maternity. Using a pool of the six available waves of individual information from the European Household Panel for Spain, we find that holding temporary contracts rather than permanent ones delays marriage for males, but not for females. Concerning maternity, the labor market situation of both members of the household affects entry into motherhood. In particular, if woman has a temporary contract rather than a permanent one, motherhoods is delayed independently of the husband's contract. As expected, postponement of maternity is not found for non-working women. These results give strong support to the career planning, motive to delay maternity in Spain, given that an unstable labor market situation of female workers is found to be the main deterrent to entry into motherhood.

Embedding ORCID Across Researcher Career Paths

Northumbria University final Jisc-ARMA ORCID pilot summary